I have a script here that will fix the problem, give it a try.
http://www.paulsxp.com/forum/viewtopic.php?f=10&t=34
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Windows XP and Vista Tweaks
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www.paulsxp.com
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Windows XP and Vista Help Forum
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www.paulsxp.com/forum
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<(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On Thu, 3 Sep 2009 19:06:04 -0500, pigpen00 <(E-Mail Removed)>
> wrote:
>
>>
>>PS: I've also clicked on Customize Notification Icons and the Volume
>>icon is missing under both Current and Past Icons, so I can't activate
>>it from there. I've also checked the Task Bar & Start Menu Properties,
>>only to find that Volume is greyed out. I don't know if that will help
>>someone identify the problem or not. I know I can probably do a system
>>restore, but I'd like to know why this is happening, if possible. Thanks
>>to anyone who can provide some insight.
>
> This continues to happen to me. I'm using Vista Home Premium. If you
> right click in the notification area>Properties, you will see check
> boxes - one of which is for the sound icon. On my PC, all four boxes
> were greyed out. No problems in Device manager. While rebooting, I
> notices that my sound icon (lit up on my keyboard) was red (meaning it
> was shut off). I pressed it until it showed white - and my sound
> returned. However, this doesn't explain why my other three boxes were
> greyed out (clock, network and power). There's still a problem
> somewhere. Until we figure it out (or someone else does), try
> rebooting.